White Labs WLP540 Abbey IV Ale Yeast is an authentic traditional style yeast with medium fruit character. It is used for Belgian style ales, dubbels, tripples, and specialty beers. White Labs yeast is world-renowned for quality and innovation, certified kosher, and subject to thorough quality analysis before being packaged. This yeast comes packaged in White Labs' PurePitch packaging using the revolutionary FlexCell process, which creates yeast that has never been transferred or exposed to the environment. The PurePitch packaging is a recyclable, flexible material that allows for increased breathability, reducing the chance of gas buildup and maintaining the optimal environment for yeast.